As robot tasks in space, nuclear, and medical environments become more widespread, the issues of reliability and safety for robots are becoming more critical. Attempts to address these issues have resulted in a a recent surge of activity in robot fault tolerance. We concentrate on fault tolerance in the robot controller, and highlight the importance and potential of multiprocessor control architectures from the fault tolerance perspective. The issue of performance versus reliability is discussed. This paper also summarizes other work by our group at Rice University in the area of fault tolerance for robotics.